GPS system to gain two signals in 2005

By Bob Brewin

Mar 29, 1998

Vice President Al Gore said a joint military/civilian board agreed to add two additional signals for civil users to Global Positioning System (GPS) satellites slated to go into service in 2005. "The additional civilian signals will significantly improve navigation, positioning and timing services to millions of users worldwide,'' Gore said. He added that the United States will provide these signals free of charge to anyone in the world equipped with a GPS receivers. The current family of 24 GPS satellites offers two military signals and one civil signal, and the Pentagon degrades the accuracy of the civil signal to provide location and position information within roughly 100 yards vs. 23 to 33 feet for military users.

Gore did not detail the accuracy that the new civil signals will offer, but a statement by the Transportation Department, which represents the interests of civil users on the Interagency GPS Executive Board, said the new signals will "greatly enhance the reliability and robustness of civilian GPS receivers by enabling them to make more robust corrections for the distorting effect of the earth's atmosphere on signals from space.''

Secretary of Transportation Rodney Slater said, "The new signals will have profound effects on the civilian transportation system and the people who use it, saving time, cutting costs, enhancing safety and providing unprecedented mobility.'' DOT plans to use GPS signals as an essential component of future air navigation systems. The Coast Guard uses augmented GPS signals to provide navigation aids for ports and rivers, while the Federal Highway Administration has numerous ongoing demonstration projects to integrate GPS into auto, truck and bus positioning and navigation systems.

Developed by the Defense Department at a cost of more than $10 billion, GPS has grown from its original purpose of providing precise navigation for weapons system into an information utility. The companies that manufacture GPS receivers have ramped volumes up to the point that the price of handheld GPS receivers is now down to $100 or less per unit.